Vote for your favorite mineral in #MinCup26! - Sphalerite vs. Anorthite
Both zinc ore Sphalerite and calcium plagioclase feldspar Anorthite have perfect cleavage that will split cleanly if you hit them with a hammer, but only one can claim a larger split of your votes!
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Alta Claim, Thunder Creek Mining District, Skagit County, Washington, USAi
Regional Level Types
Alta ClaimDeposit
Thunder Creek Mining District- not defined -
Skagit CountyCounty
WashingtonState
USACountry

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Latitude & Longitude (WGS84):
48° 30' 10'' North , 121° 3' 52'' West
Latitude & Longitude (decimal):
48.50288,-121.06454
GeoHash:
G#: c29gvjemz
GRN:
N33W58
Type:
Deposit
Köppen climate type:
Dfc : Subarctic climate
Nearest Settlements:
PlacePopulationDistance
Marblemount203 (2011)28.5km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Darrington Rock & Gem ClubDarrington, Washington48km
Mindat Locality ID:
448686
Long-form identifier:
mindat:1:2:448686:5
GUID (UUID V4):
0
Other/historical names associated with this locality:
Helena Butte, Montreal, Cerrico


Structure: Shear Zone

Tectonics: Active Margin (Leading Edge Of North American Plate)

Deposit: A cross vein of the boston vein: quartz vein in shear zone in gneiss near diorite contact. 4 claims: alta montreal, helna butte, cerrico (record no. 700365). Boston vein is record no. M700366. ; info.src : 1 pub lit see also mrds record m700365

Deposit type: Polymetallic veins

Rock formation(s): Eldorado Orthogneiss


Ore(s): Shear Zone

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Commodity List

This is a list of exploitable or exploited mineral commodities recorded at this locality.


Mineral List


3 valid minerals.

Rock Types Recorded

Note: data is currently VERY limited. Please bear with us while we work towards adding this information!

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Alphabetical List Tree Diagram

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
ⓘSphalerite2.CB.05aZnS
ⓘGalena2.CD.10PbS
ⓘPyrite2.EB.05aFeS2

List of minerals for each chemical element

SSulfur
Sⓘ GalenaPbS
Sⓘ PyriteFeS2
Sⓘ SphaleriteZnS
FeIron
Feⓘ PyriteFeS2
ZnZinc
Znⓘ SphaleriteZnS
PbLead
Pbⓘ GalenaPbS

Other Databases

Link to USGS MRDS:10047984

Other Regions, Features and Areas containing this locality

North AmericaContinent

This page contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders for access and that you are aware of all safety precautions necessary.
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